The question of "Why Seven Meters" is a really good one. And there is a good answer for this. But the answer requires some preliminary work. Sea level changes every century as climate conditions change. After an ice age, sea level will rise as the glaciers shrink. As another ice age grows, sea level will fall as water is captured on the continents. Between ice ages, continents rise as well when released from the weight of thousands of feet of ice. Without human intervention, we would likely see the trend of slow sea level rise continue as it has for centuries.